1. Field of the Invention
The present invention relates to a magnetic disc apparatus using a lubricant supply head-disc interface method that supplies lubricant to a magnetic disc platter from a specific lubricant supply source. Particularly, it relates to a lubricant whose average molecular weight measures in a specific range in order to obtain high reliability for a long period of time using inner portions of the apparatus as a lubricant supply source. It also relates to a fabricating method of the apparatus having the lubricant.
2. Description of the Related Art
A technique for supplying lubricant to a magnetic disc platter in a magnetic disc apparatus and for specially arranging a lubricant supply mechanism for supplying lubricant utilizing hot air in an apparatus on a base under a spindle is disclosed in Japanese published examined patent application No. Hei 1-21557. In such a case, the structure of the magnetic disc apparatus becomes complex and the method of assembling the apparatus becomes more complex, thereby increasing cost and deteriorating productivity.
A magnetic disc apparatus characterized in that lubricant of the same group as lubricant applied to a magnetic disc is applied to a bearing of an actuator, a guide rail or a bolt fastened part is also proposed in Japanese published examined patent application No. Hei 7-82698. Recently, with respect to lubricants applied on a magnetic disc, fluoric lubricant having an end functional group is used and is very expensive. When lubricant in the same group as lubricant applied to a magnetic disc is used for a mechanically worn part in a magnetic disc apparatus, a large quantity of lubricant is required and the increase in cost becomes unavoidable.
Also, in the above-mentioned two prior art references, the molecular weight of the lubricant, which is most important when considering a lubricant supply method, is not defined. Therefore, these references do not sufficiently disclose how to adequately secure high reliability, which is of utmost importance for a magnetic disc apparatus in the long term.